This invention relates to reducing drag in over-the-road vehicles (including trucks and passenger car) to make them more fuel efficient; and, more particularly, to a cowling, shroud, or fairing (collectively, a cowling) which is installed over the radiator of the vehicle to improve the vehicle's aerodynamic characteristics.
It is well known that over the road trucks, semis and the like, have low fuel efficiency. Typically, these tractor trailer vehicles attain about five to seven miles per gallon (5-7 mpg) when traveling at highway speeds of, for example, 50-70 miles per hour (mph). One reason for this is the aerodynamic characteristics of these vehicles and their high coefficient of drag. A number of attempts have been made to improve the aerodynamics of these vehicles in order to improve gas mileage. Fairings with curved surfaces have been mounted on top the vehicle's cab to create a smoother air flow over the top of the vehicle. Other devices have also been installed on the vehicles for this purpose.
However, a major contributor to the vehicle's drag is the blunt front end of the truck where the radiator is located. The radiator, which is generally rectangular in shape, extends vertically from an area adjacent the truck's from bumper to the top of its hood. It also extends horizontally across a good portion of the front end of the track. As the truck moves over the road, air strikes the radiator and is forced either over or under the top and bottom of the radiator, and about it sides. This, in turn, creates a drag which significantly impacts the trucks forward movement and increases its fuel consumption.
With regard to the above described problem, it is known to use spoilers or air dams to help reduce drag. However, these are typically static devices which provide a limited amount of help in reducing drag. Further, these devices are specific to the particular vehicle on which they are installed. It would be valuable and advantageous to have a structure (cowling, fairing, shroud, air dam or the like) as either original equipment (OE) or as a retrofit which is adjustable so to reduce the drag encountered in a variety of situations and in which, even if only one particular design is usable on a particular vehicle, its operation can be adjusted to accommodate any differences between vehicles of the same type.
While passenger cars and similar vehicles do not create the same amount of drag as trucks when they travel at highway speeds, use of a cowling of the present invention on them will also improve their fuel efficiency.